Sessile
Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that lack a stalk * Sessility (in crystallography), dislocation that is not able to move in the slip plane (as opposed to glissile) See also * Sedentism In cultural anthropology, sedentism (sometimes called sedentariness; compare sedentarism) is the practice of living in one place for a long time. , the large majority of people belong to sedentary cultures. In Sociocultural evolution, evolutio ...

Sessility (motility)
Sessility is the biological property of an organism describing its lack of a means of self-locomotion. Sessile organisms for which natural ''motility'' is absent are normally immobile. This is distinct from the botanical concept of sessility, which refers to an organism or biological structure attached directly by its base without a stalk. Sessile organisms can move via external forces (such as water currents), but are usually permanently attached to something. Organisms such as corals lay down their own substrate from which they grow. Other sessile organisms grow from a solid such as a rock, dead tree trunk, or a man-made object such as a buoy or ship's hull. Mobility Sessile animals typically have a motile phase in their development. Sponges have a motile larval stage and become sessile at maturity. Conversely, many jellyfish develop as sessile polyps early in their life cycle. In the case of the cochineal, it is in the nymph stage (also called the crawler stage) that the ...
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Sessility (botany)
In botany, sessility (meaning "sitting", used in the sense of "resting on the surface") is a characteristic of plant parts (such as flowers and leaves) that have no stalk. Plant parts can also be described as subsessile, that is, not completely sessile. A sessile flower is one that lacks a pedicel (flower stalk). A flower that is not sessile is pedicellate. For example, the genus ''Trillium'' is partitioned into two subgenera, the sessile-flowered trilliums (''Trillium'' subg. ''Sessilium'') and the pedicellate-flowered trilliums. Sessile leaves lack petioles (leaf stalks). A leaf that is not sessile is petiolate. For example, the leaves of most monocotyledons lack petioles. The term sessility is also used in mycology to describe a fungal fruit body that is attached to or seated directly on the surface of the substrate, lacking a supporting stipe or pedicel Pedicle or pedicel may refer to: Human anatomy *Pedicle of vertebral arch, the segment between the transvers ...
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Sessility (medicine)
A peduncle is an elongated stalk of tissue. Sessility is the state of not having a peduncle; a sessile mass or structure lacks a stalk. In medicine, a mass such as a cyst or polyp is said to be ''pedunculated'' if it is supported by a peduncle. There are in total three types of peduncles in the cerebellum of the human brain, known as superior cerebellar peduncle, middle cerebellar peduncle, and inferior cerebellar peduncle. Pedunculated eyes are also the defining attribute of the Stylophthalmine trait found in certain fish larvae. The caudal peduncle is a slightly narrowed part of a fish where the caudal fin meets the spine. See also *Peduncle (botany) In botany, a peduncle is a stalk supporting an inflorescence or a solitary flower, or, after fecundation, an infructescence or a solitary fruit. The peduncle sometimes has bracts (a type of cataphylls) at nodes. The main axis of an inflorescenc ... References Gross pathology {{anatomy-stub ...
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Dislocation
In materials science, a dislocation or Taylor's dislocation is a linear crystallographic defect or irregularity within a crystal structure that contains an abrupt change in the arrangement of atoms. The movement of dislocations allow atoms to slide over each other at low stress levels and is known as ''glide'' or slip. The crystalline order is restored on either side of a ''glide dislocation'' but the atoms on one side have moved by one position. The crystalline order is not fully restored with a ''partial dislocation''. A dislocation defines the boundary between ''slipped'' and ''unslipped'' regions of material and as a result, must either form a complete loop, intersect other dislocations or defects, or extend to the edges of the crystal. A dislocation can be characterised by the distance and direction of movement it causes to atoms which is defined by the Burgers vector. Plastic deformation of a material occurs by the creation and movement of many dislocations. The number and a ...
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